Without you even realising, your garden could contain a thug of the plant world, a thug which spreads like wildfire and is so invasive it could wreck your chances of selling your home.

The name of this terrible thug? Japanese knotweed.

This clump-forming perennial produces stems similar to bamboo that can grow to a height of 3m or more at a phenomenal rate – 1m in just a month – and that’s not the only problem.

As well as growing fast, it’s extremely invasive, reproduces very easily and is difficult and expensive to get rid of for good.

Japanese knotweed reproduces and spreads through its stem, crown and creeping underground stems (rhizomes) – even a small piece can become a new plant.

The plants are capable of breaking through tarmac and weak points in concrete and of causing substantial structural damage to buildings. They overwhelm other garden plants, which is bad for wildlife, and can increase the risk of soil erosion and flooding. Japanese knotweed can even ‘play dead’ – rhizomes can stay dormant underground for as long as 20 years before producing plants.

The above-ground stems grow densely and have an unusual purple speckle, before turning brown and dying back in winter. Small flowers appear in late summer and early autumn, and are actually so attractive that it was introduced to this country by the Victorians as an ornamental plant – little did they know the chaos it would cause.

And, yes, one aspect of that chaos is scuppering house sales. If the plant is found by the surveyor during the valuation, the mortgage provider may refuse to lend on the property, or may make a retention – property sales and chains have collapsed because of it.

If you’re already a homeowner though, and think Japanese knotweed is growing in your garden, don’t panic – eradicating it isn’t an easy job, but it can be done. While it isn’t an offence to have it on your land and you’re not legally obliged to remove it, unless it’s causing a nuisance to your neighbours’ properties or is spreading into the wild, you’d be extremely unwise not to take action.

You never know when you may have to sell your home, so if you think you have this menace lurking in your garden, act immediately and get it right first time by employing an expert.